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Emissions System & Component Test Parameters

EVAP SYSTEM OPERATION

Components & Conditions Specification
Ignition Switch Off
Coolant Temp. N/A
Thermo Temp. N/A
Engine RPM N/A
Throttle Position Switch N/A
VSV N/A
Canister Check Valve
(1) N/A
(2) N/A
Check Valve In Fuel Filler Cap N/A
Evaporation Fuel (HC) HC from tank & float chamber is absorbed into the canister
Ignition Switch On, High vacuum in tank
Coolant Temperature N/A
Thermo. Temperature N/A
Engine RPM N/A
Throttle Position Switch N/A
VSV N/A
Canister Check Valve
(1) Closed
(2) Open
Check Valve in Fuel Filler Cap Open
Evaporation Fuel (HC) Air is led into the tank
(1) With outer vent control valve open.
(2) With outer vent control valve closed..
CARBURETOR FEEDBACK SYSTEM OPERATION

Components & Conditions Specification
Coolant Temp. Below 63°F (17°C)
TVSV Open (K-L)
Condition N/A
Deceleration - Engine RPM Above 1500 RPM
TPS Off
Vacuum Switch On
Air Fuel Ratio in the Exhaust Manifold N/A
O2 Sensor Signal N/A
Computer On
EBCV Open
Air Bleed On
DECELERATION FUEL CUT-OFF SYSTEM OPERATION

Components & Conditions Specification
Engine RPM Less than 1600 RPM
Throttle Position Switch On
Computer Off
Primary Fuel Cut Solenoid Valve On
Slow Circuit in Carburetor Open
Engine RPM More than 2000 RPM
Throttle Position Switch Off
Computer Off
Primary Fuel Cut Solenoid Valve Off
Slow Circuit in Carburetor Closed
COLD MIXTURE HEATER OPERATION

Components & Conditions Specification
Ignition Switch Off Engine Not Running
Coolant Temp. N/A
Thermo Switch N/A
ECM N/A
CMH Relay Off
CMH Off
Ignition Switch On Engine Not Running
Coolant Temp. N/A
Thermo Switch N/A
ECM Off
CMH Relay Off
CMH Off
Ignition Switch Off Engine Running
Coolant Temp. Below 109°F (43°C)
Thermo Switch On
ECM On
CMH Relay On
CMH On (Heated)
Ignition Switch On Engine Running
Coolant Temp. Below 109°F (43°C)
Thermo Switch On
ECM On
CMH Relay On
CMH On (Heated)
Ignition Switch On Engine Running
Coolant Temp. Above 131°F (55°C)
Thermo Switch Off
ECM Off
CMH Relay Off
CMH Off